CHARACTERS OF THE RASORIAL TYPE. 263 
portant article of food ; while the bird called by Le 
Vaillant the Jmportan, accompanies him in his woodland 
rambles.* All these instincts are evident modifications 
of one and the same principle ; and this is so strong, 
that it is sometimes extended to the indirect repre- 
sentations of rasorial types in other groups: hence we 
find that the swallows, although a natatorial type, 
always build, by preference, in the vicinity of human 
habitations ; there being a parallel analogy between this 
family and the rasorial parrots (Psittacide). Yet not 
one of the natatorial types can be domesticated. 
(321.) That the characters of the rasorial type may 
be rendered more apparent, we shall now bring before 
the reader a more condensed enumeration of the chief 
types in which they are conspicuous ; leaving him to in- 
vestigate, through the natural history of the animals 
themselves, the degree of analogy they respectively 
possess. These rasorial types are arranged in columns, 
indicating the developement of each of those rasorial 
characters which have already been explained. To 
those who, in a good or in a captious spirit, have ob- 
jected, that we are perpetually talking of demonstration, 
when not one demonstration in these volumes has yet 
been given, we shall here, once for all, address a few 
words. Wherever in this, or in the Preliminary Dis- 
course, such an appeal has been made, we have referred 
to the previous and well-known labours of Mr. Mac- 
Leay and of others, or to our own in the work so often 
quoted.t No demonstration is, or was intended to be, 
given in that volume ; nor is there one in this, because 
such proof depends upon analysis, and not one group of 
animals has yet been analysed in these volumes. Results 
of previous analysis, indeed, have been often quoted, as 
at p. 234. When, therefore, the supposed errors of the 
* Oiseaux d’ Afrique, vol. iii. p.41. Andropadus viridis Sw., N. Z00}. 485. 
+ Had one of our reviewers known any thing of the Fauna Boreali- 
Americana, beyond the title-page, he would not have asked why constant 
reference was made to that volume rather than to W7/son’s American Orni- 
thology : the first containing all those demonstrations of the ornithological, 
groups to which we have appealed ;_ while the latter, as every one knows, 
is a mere history of species. 
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